UrbanTick has also started looking into the technique with their first clip based around the UrbanDiary project, recorded between April and August 2009:
If you want to do these yourself a good start is to take a look at http://www.learningprocessing.com/ Daniels book at the site is one of the best tutorial books we have read in a while.
Also, Visualizing Data by Ben Fry is a good second step, link this with an Arduino Unit and things begin to get interesting in terms of the possibilities for interaction and visualistion of the urban environment.
We will have more on linking Ardunio, Processing and general visualisation in future posts.